[qtwebkit] Prefer width in viewport minimum scale calculations
[qtwebkit] Add experimental header component
[qtwebkit] Reset rendering/scale state back to default when loading starts.

First frame rendered, relayout requested and fixed layout size
needs to be reset back to original state when loading starts. This
fixes issues of scaling pages when url/html is changes.
Merge pull request #6 from rainemak/viewportAndHeader

Viewport and header